Advancements in water decontamination technologies: a special emphasis on adsorption techniques
摘要
Water contamination remains a significant global concern, exacerbated by industrialization, agriculture, and population growth. Among various treatment strategies, adsorption has emerged as the most practical and sustainable method due to its simplicity, scalability, and versatility. Recent advances include nanostructured adsorbents, hybrid composites, and bio-derived materials, achieving 80–99% removal of dyes, heavy metals, and pharmaceuticals. Significant regional progress has also been reported in Africa, particularly Nigeria, where low-cost precursors such as coconut shells, rice husks, and cassava peels demonstrated removal efficiencies of 78–98% for Pb2⁺, Cd2⁺, and Cr6⁺. Mechanistic insights into physisorption and chemisorption, supported by kinetic and isotherm models, have further improved adsorption process optimization. Despite these achievements, major challenges remain, including limited regenerability, reduced selectivity in multi-contaminant systems, fouling and leaching risks, variability of bio-derived feedstocks, and energy or cost constraints during large-scale application. The review concludes by recommending intensified research into multifunctional, regenerable, and environmentally benign adsorbents, supported by mechanistic modelling and real-world validation to enable sustainable water treatment solutions globally.